The ability to double our biomass - not by waiting several million years and growing to be the size of an elephant - but waiting a few hundred thousand years for neurons to sprout into our brains - ones capable of having us create emotional relationships with other members of our species. We thereby double our biomass not by getting bigger, but by creating an ally.

We are human because we can fantasize.

Don't start with the details. Start with the key ideas, and in a hierarchical fashion, form the details around these larger notions.

There is a neuron in your brain that will respond only to pictures of Jennifer Aniston - provided you have had prior visual exposure to the actress. That neuron does not respond to pictures of Bill Clinton or Halle Berry. Only Jennifer. I used the story to explain the almost ridiculous plasticity of the organ. There is no such thing as Jennifer Aniston in our evolutionary history - she was born in 1969, for heaven's sake - but we are flexible enough to devote an entire cell to her if we have previously encountered her in some fashion.

The brain appears to have been designed to solve problems related to surviving in an outdoor setting, in unstable meteorological conditions, and to do so in near constant motion.

The brain doesn't care about change. As the world's most sophisticated survival organ, the brain cares about loss.

The brain processes meaning before detail. Providing the gist, the core concept, first was like giving a thirsty person a tall glass of water. And the brain likes hierarchy. Starting with general concepts naturally leads to explaining information in a hierarchical fashion. You have to do the general idea first. And then you will see that 40 percent improvement in understanding.